Refrigerator dehydrator



13, 1956 E. w. BOTTUM 2,770,317

REFRIGERATOR DEHYDRATOR Filed Oct. 1, 1953 INVENTOR.

wmwo 14 8077044 284 BY -rv-r/n /fazsm/ United States Patent REFRIGERATORDEHYDRATOR Edward W. Bottum, Detroit, Mich.

Application October 1, 1953, Serial N 0. 383,534

ll Claim. (Cl. 183--4.8)

The present invention relates to a dehydrator and accumulator for arefrigeration system which is designed and adapted to maintain therefrigerant substantially free from moisture at all times.

The present invention is an improvement over thedevice disclosed in myprevious United States Letters Patent No. 2,623,607, issued December 30,1952, for a refrigeration dehydrator. In that device, the desiccant,such as silica gel, is contained in a mesh bag placed within acylindrical container through which the refrigerant passes. Prior tothis invention the desiccant had been loose within the container. I havefound, however, that in my previous device, the flow of the refrigeranttends to buffet the bag of desiccant with the result that some powderingof the granules of desiccant contained in said bag has been observed.For this reason it has been found desirable to use a very fine meshmaterial in the bag construction to prevent the powdered desiccant fromentering the refrigerant stream. Also, the bag of desiccant is subjectedto similar buffeting during shipment and storage of the dehydrator.

In order to overcome this problem I have developed the novel dehydratorof the present invention wherein the mesh bag containing the dessicantis firmly held within the dehydrator casing by a novel spring retainingmeans which is integral with the desiccant bag and engages the innerwalls of the dehydrator to prevent shifting of the desiccant bag withinthe dehydrator casing.

I have also found that it is desirable to use a wire or spring cliparound the bag longitudinally to compress the desiccant therein andprevent rattling thereof within the bag itself.

Further, I have discovered that it is advantageous to insert a plug ofglass wool or metal wool in one or both ends of the bag prior to scalingthe ends thereof. The plug insulates the desiccant from the ends of thebag so that when the ends are sealed, such as by welding or soldering,the desiccant is not subjected to the heat inwolved. The plug alsoserves as a baffle as the refrigerant enters the end of the bag tofacilitate dispersing the refrigerant stream and directing it moreevenly through the desiccant, as well as absorbing the force of therefrigerant stream thereby diminishing the buffeting of the desiccantwithin the bag. The plug at the opposite end of the bag will serve tofilter the refrigerant stream as it passes therethrough removing anyfine particles of desiccant which may be included therein. The plugsalso serve as cushions to firmly retain the desiccant within the meshbag.

I have found that with these improvements 1 am able to use a coarsermesh in the desiccant bag which in turn reduces the cost of manufactureof the dehydrator. The coarser mesh also allows more of the refrigerantto flow through the bag instead of passing therearound and also reducesthe resistance of the bag to the refrigerant flow thereby decreasing thepressure drop through the dehydrator.

It is accordingly one object of the present invention to provide arefrigerant dehydrator for use in a refrigeration system wherein thedehydrating material is contained in 2 a mesh bag disposed in thedehydrator casing so that the refrigerant will circulate freely throughthe dehydrator without breaking down the particles of the dehydratingmaterial to the end that no fine particles of the desiccant areintroduced into the refrigerant stream to clog the dehydrator or otherelements of the refrigeration system.

Another object of the present invention is to provide such a dehydratorwherein the mesh bag disposed therein is provided with a novel springretaining means to firmly hold said bag within the dehydrator shell andprevent relative movement thereof during shipment and storage of thedehydrator or relative movement of the bag by the refrigerant streamduring the use thereof.

Still another object of the present invention is toprovide such arefrigeration dehydrator wherein glass wool or metal wool plugs areinserted in the ends of the mesh bag so as to insulate the desiccantfrom the heat used in sealing the ends of said bag, to cushion thedesiccant within the bag and prevent powdering thereof, to disperse therefrigerant stream through said bag and desiccant to absorb the force ofthe refrigerant flow and to filter the refrigerant as it passes out ofsaid bag.

A further object of the present invention is to provide such arefrigeration dehydrator wherein the mesh bag containing the desiccantis provided with a wire or spring clip longitudinally therearound tocompress the desiccant therein and prevent rattling thereof within thebag.

Other objects of this invention will appear in the following descriptionand appended claim, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

In the drawings:

Figure l is a plan view of one embodiment of the present invention withthe near side of the dehydrator casing broken away to show the desiccantbag disposed therein and a portion of the desiccant bag broken away toshow an end plug therein,

Fig. 2 is an end view showing one of the end caps of the dehydrator ofthe present invention,

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 1,

Fig. 4 is an end view of the other end cap of the dehydrator of thepresent invention,

Fig. 5 is a view similar to Fig. 1 showing a second embodiment of thepresent invention,

Fig. 6 is a plan view of the longitudinal spring clip shown in positionon the desiccant bag in Fig. 5, and

Fig. 7 is a side View of one end of the desiccant bag showing the methodof closing the end thereof.

Before explaining the present invention in detail, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Also,it is -to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

Referring to Fig. 1, the refrigeration dehydrator and accumulator of thepresent invention comprises the cylindrical casing 10 having the endcaps 12 and 14 thereon. As can be seen the end caps 12 and 14 have thetube portions 16 and 18 respectively projecting therefrom which aresecurely fitted thereto and form an integral part thereof.

A wire mesh bag 20 is disposed within the casing 10 and contains adesiccant material 22, such as silica gel, in granular form. The meshbag 20 is formed of Monel metal or similar non-corrosive material whichis inert to the desiccant and the refrigerant.

Either one or both ends of the mesh bag 20 is provided with a plug 24 ofglass wool or metal wool such as copper,

brass, and aluminum. This plug 24 is inserted after the desiccant hasbeen placed in the bag and the ends of the bag are then folded over andfastened by any suitable means such as by soldering or welding. The plugalso keeps the desiccant from the end fold thereby preventing itsinterfering with the soldering as well as insulating the desiccant fromthe end of the bag so that when the bag is soldered the heat does notreach the desiccant.

The plug 24 also serves to cushion the desiccant Within the bag 20thereby preventing rattling of the desiccant which would result in fineparticles breaking off and being carried by the refrigerant stream whenthe dehydrator is placed in service. Further, the plug 24 Whenpositioned adjacent the inlet end of the dehydrator, will serve to bamethe gaseous refrigerant stream and direct it more evenly through thedesiccant while at the same time absorbing the force of the refrigerantflow thereby preventing the refrigerant stream from buffeting thedesiccant particles within the bag 20. When the plug 24 is positionedadjacent the outlet end of the dehydrator it serves to filter any fineparticles of desiccant or foreign matter which may have been absorbedinto the refrigerant stream.

It is to be understood that I contemplate providing a plug 24 at eitherone or both ends of the mesh bag 20 within the scope of the presentinvention.

Referring again to Fig. 1, the novel spring retaining means for holdingthe bag 20 within the casing 10 can be seen. As shown in Fig. 7, whenthe ends of the bag are folded over and soldered as at 23 a channel 25is formed to receive the spring wire 26. This spring wire is somewhatlonger than the diameter of the casing 10 so that it will bend as shownwhen the bag is inserted into the casing and the ends of the spring wire26 engage the inner wall of the casing 10 as shown in Fig. 1. A similarspring may be provided at both ends of the bag 20. Thus, the bag is heldfirmly in position within the casing 10 by the spring 26 so that duringshipment or storage of the dehydrator the bag will not rattle and powderthe desiccant. Also, when the dehydrator is placed in service, therefrigerant flow will not buffet the bag about within casing 10.

It can be seen that the folding over of the bag ends and theme of thespring 26 gives the filler bag 20 the general shape of a pillow with thecorners projecting slightly from the main body thereof to engage thecasing 10. The bag is also made shorter in length than the length of theeasing 10 so that space is provided completely around the bag 20 whichalso insulates the bag from the casing. Consequently, upon soldering ofthe end caps 12 and 14 to the casing 10, the desiccant within the bag 20is held far enough away from the casing to prevent the heat of thesoldering operation from breaking down the desiccant. This space alsoprovides a bypass for a certain amount of i the refrigerant flow so thatthere will be no material pressure drop through the dehydrator.

A wire 28 (Fig. 1) is fastened longitudinally around the mesh bag 20.This wire serves to compress the desiccant within the bag and preventrattling thereof. The wire also serves somewhat to aid in retaining thepillow shape of the bag 20 and in bowing the spring 26. In theembodiment shown in Figs. 5 and 6 the spring clip 28A is provided toserve the same purpose as wire 28 of Figs. 1 and 3. The embodiment shownin Fig. 5 is similar in all other respects to that shown in Figs. 1 and3.

While I have illustrated in the drawings a wire mesh bag having one endplug 24, a spring retainer means 26 in only one end of the bag, and alongitudinal wire 28 or spring clip 28a, it is to be understood that itis within the contemplation of the present invention to utilize a plug24 at each end of the bag 20 and a spring 26 at each end also. Furtherit is to be understood that when the plugs 24 are used it may in someinstances be possible "to omit the use of the longitudinal wire 28 orspring clip 28A as the desiccant may then be sufficiently cushionedwithin the bag 20 and firmly held therein.

From the above it can be seen that I have provided a novel refrigerationdehydrator and accumulator wherein the desiccant is contained within amesh bag within the device in such a manner as to prevent powdering ofthe desiccant and a novel spring retaining means has been provided tofirmly retain the mesh bag.

Also, it can be seen that my novel construction prevents the powderingof the desiccant and therefore allows the use of a coarser mesh bag thanin previous constructions thereby decreasing the cost of my device andalso decreasing the pressure drop through the dehydrator and accumulatorwhen it is utilized in a refrigeration system.

Having thus described my invention, I claim:

In a dehydrator adapted for placement in a refrigerating system todehydrate a refrigerant and comprising a hollow casing having inlet andoutlet means and a wire mesh bag containing a granular desiccantdisposed there- 'in, the improvement consisting of a spring wirepositioned in a channel formed by folding and fastening the end of saidbag, said spring wire being slightly bowed With the ends thereofengaging the inner wall of said container to firmly position said bagwithin said container and prevent movement of said bag relative to saidcontainer thereby preventing the powdering of said desiccant.

References Cited in the file of this patent UNITED STATES PATENTS2,507,028 Lockwood May 9, 1950 2,556,292 Newcum June 12, 1951 2,593,132Gannon Apr. 15, 1952 2,623,607 Bottum Dec. 30, 1952 2,625,360 Hall Jan.13, 1953

